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 Android教程網 >> Android技術 >> 關於Android編程 >> Android 開源框架Universal-Image-Loader實例分析

Android 開源框架Universal-Image-Loader實例分析

編輯：關於Android編程

 

主要分析官方的demo，以及一些需要注意的東西

1，首先，三個頁面

HomeActivity（首頁，注意有清空緩存的菜單鍵）

SimpleImageActivity（listview，gridview，gallery，viewpage等都在此頁面，通過不同的fragment顯示）

ComplexImageActivity（通過viewpage混和了listview和gridview的頁面）

首頁

 

/*******************************************************************************
 * Copyright 2011-2013 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.activity;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.sample.Constants;
import com.nostra13.universalimageloader.sample.R;
import com.nostra13.universalimageloader.sample.fragment.ImageGalleryFragment;
import com.nostra13.universalimageloader.sample.fragment.ImageGridFragment;
import com.nostra13.universalimageloader.sample.fragment.ImageListFragment;
import com.nostra13.universalimageloader.sample.fragment.ImagePagerFragment;
import com.nostra13.universalimageloader.utils.L;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
public class HomeActivity extends Activity {

	private static final String TEST_FILE_NAME = Universal Image Loader @#&=+-_.,!()~'%20.png;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.ac_home);

		File testImageOnSdCard = new File(/mnt/sdcard, TEST_FILE_NAME);
		if (!testImageOnSdCard.exists()) {
			copyTestImageToSdCard(testImageOnSdCard);
		}
	}

	public void onImageListClick(View view) {
		Intent intent = new Intent(this, SimpleImageActivity.class);
		intent.putExtra(Constants.Extra.FRAGMENT_INDEX, ImageListFragment.INDEX);
		startActivity(intent);
	}

	public void onImageGridClick(View view) {
		Intent intent = new Intent(this, SimpleImageActivity.class);
		intent.putExtra(Constants.Extra.FRAGMENT_INDEX, ImageGridFragment.INDEX);
		startActivity(intent);
	}

	public void onImagePagerClick(View view) {
		Intent intent = new Intent(this, SimpleImageActivity.class);
		intent.putExtra(Constants.Extra.FRAGMENT_INDEX, ImagePagerFragment.INDEX);
		startActivity(intent);
	}

	public void onImageGalleryClick(View view) {
		Intent intent = new Intent(this, SimpleImageActivity.class);
		intent.putExtra(Constants.Extra.FRAGMENT_INDEX, ImageGalleryFragment.INDEX);
		startActivity(intent);
	}

	public void onFragmentsClick(View view) {
		Intent intent = new Intent(this, ComplexImageActivity.class);
		startActivity(intent);
	}

	@Override
	public void onBackPressed() {
		ImageLoader.getInstance().stop();
		super.onBackPressed();
	}

	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		getMenuInflater().inflate(R.menu.main_menu, menu);
		return true;
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
			case R.id.item_clear_memory_cache:
				ImageLoader.getInstance().clearMemoryCache();
				return true;
			case R.id.item_clear_disc_cache:
				ImageLoader.getInstance().clearDiskCache();
				return true;
			default:
				return false;
		}
	}

	private void copyTestImageToSdCard(final File testImageOnSdCard) {
		new Thread(new Runnable() {
			@Override
			public void run() {
				try {
					InputStream is = getAssets().open(TEST_FILE_NAME);
					FileOutputStream fos = new FileOutputStream(testImageOnSdCard);
					byte[] buffer = new byte[8192];
					int read;
					try {
						while ((read = is.read(buffer)) != -1) {
							fos.write(buffer, 0, read);
						}
					} finally {
						fos.flush();
						fos.close();
						is.close();
					}
				} catch (IOException e) {
					L.w(Can't copy test image onto SD card);
				}
			}
		}).start();
	}
}

 

 

SimpleImageActivity

除了HomeActivity和ComplexImageActivity，其他界面都在此顯示
根據不同的標簽生成不同Fragment......最後commit，確認顯示
ImagePagerFragment標簽下需要保存下列表Fragment傳過來的條目position的數據，給ImagePagerFragment（實際上這個跳轉是從SimpleImageActivity跳到SimpleImageActivity，有點怪）

 

/*******************************************************************************
 * Copyright 2014 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.activity;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import com.nostra13.universalimageloader.sample.Constants;
import com.nostra13.universalimageloader.sample.R;
import com.nostra13.universalimageloader.sample.fragment.ImageGalleryFragment;
import com.nostra13.universalimageloader.sample.fragment.ImageGridFragment;
import com.nostra13.universalimageloader.sample.fragment.ImageListFragment;
import com.nostra13.universalimageloader.sample.fragment.ImagePagerFragment;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
//除了主界面和組合了listview和gridview的界面，其他界面都在此顯示
//根據不同的標簽生成不同Fragment......最後commit，確認顯示
//ImagePagerFragment標簽下需要保存下列表Fragment傳過來的條目position的數據，給ImagePagerFragment（實際上這個跳轉是從SimpleImageActivity跳到SimpleImageActivity，有點怪）
public class SimpleImageActivity extends FragmentActivity {
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		int frIndex = getIntent().getIntExtra(Constants.Extra.FRAGMENT_INDEX, 0);
		Fragment fr;
		String tag;
		int titleRes;
		switch (frIndex) {
			default:
			case ImageListFragment.INDEX:
				tag = ImageListFragment.class.getSimpleName();
				fr = getSupportFragmentManager().findFragmentByTag(tag);
				if (fr == null) {
					fr = new ImageListFragment();
				}
				titleRes = R.string.ac_name_image_list;
				break;
			case ImageGridFragment.INDEX:
				tag = ImageGridFragment.class.getSimpleName();
				fr = getSupportFragmentManager().findFragmentByTag(tag);
				if (fr == null) {
					fr = new ImageGridFragment();
				}
				titleRes = R.string.ac_name_image_grid;
				break;
			case ImagePagerFragment.INDEX:
				tag = ImagePagerFragment.class.getSimpleName();
				fr = getSupportFragmentManager().findFragmentByTag(tag);
				if (fr == null) {
					fr = new ImagePagerFragment();
					fr.setArguments(getIntent().getExtras());
				}
				titleRes = R.string.ac_name_image_pager;
				break;
			case ImageGalleryFragment.INDEX:
				tag = ImageGalleryFragment.class.getSimpleName();
				fr = getSupportFragmentManager().findFragmentByTag(tag);
				if (fr == null) {
					fr = new ImageGalleryFragment();
				}
				titleRes = R.string.ac_name_image_gallery;
				break;
		}

		setTitle(titleRes);
		//此時關聯的tag和對應的fragment
		getSupportFragmentManager().beginTransaction().replace(android.R.id.content, fr, tag).commit();
	}
}

ComplexImageActivity

 

 

/*******************************************************************************
 * Copyright 2014 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.activity;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import com.nostra13.universalimageloader.sample.R;
import com.nostra13.universalimageloader.sample.fragment.ImageGridFragment;
import com.nostra13.universalimageloader.sample.fragment.ImageListFragment;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
public class ComplexImageActivity extends FragmentActivity {

	private static final String STATE_POSITION = STATE_POSITION;

	private ViewPager pager;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.ac_complex);

		int pagerPosition = savedInstanceState == null ? 0 : savedInstanceState.getInt(STATE_POSITION);

		pager = (ViewPager) findViewById(R.id.pager);
		pager.setAdapter(new ImagePagerAdapter(getSupportFragmentManager()));
		pager.setCurrentItem(pagerPosition);
	}

	@Override
	public void onSaveInstanceState(Bundle outState) {
		outState.putInt(STATE_POSITION, pager.getCurrentItem());
	}

	private class ImagePagerAdapter extends FragmentPagerAdapter {

		Fragment listFragment;
		Fragment gridFragment;

		ImagePagerAdapter(FragmentManager fm) {
			super(fm);
			listFragment = new ImageListFragment();
			gridFragment = new ImageGridFragment();
		}

		@Override
		public int getCount() {
			return 2;
		}

		@Override
		public Fragment getItem(int position) {
			switch (position) {
				case 0:
					return listFragment;
				case 1:
					return gridFragment;
				default:
					return null;
			}
		}

		@Override
		public CharSequence getPageTitle(int position) {
			switch (position) {
				case 0:
					return getString(R.string.title_list);
				case 1:
					return getString(R.string.title_grid);
				default:
					return null;
			}
		}
	}
}

2，UILApplication，應用配置文件

 

可以配置默認的參數，並創建ImageLoader的實例

 

//創建默認的ImageLoader配置參數  
        ImageLoaderConfiguration configuration = ImageLoaderConfiguration  
                .createDefault(this);  
          
        //Initialize ImageLoader with configuration.  
        ImageLoader.getInstance().init(configuration);

也可以配置具體的參數

 

 

/*******************************************************************************
 * Copyright 2011-2013 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample;

import android.annotation.TargetApi;
import android.app.Application;
import android.content.Context;
import android.os.Build;
import android.os.StrictMode;

import com.nostra13.universalimageloader.cache.disc.naming.Md5FileNameGenerator;
import com.nostra13.universalimageloader.cache.memory.impl.WeakMemoryCache;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import com.nostra13.universalimageloader.core.assist.QueueProcessingType;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
public class UILApplication extends Application {
	@TargetApi(Build.VERSION_CODES.GINGERBREAD)
	@SuppressWarnings(unused)
	@Override
	public void onCreate() {
		if (Constants.Config.DEVELOPER_MODE && Build.VERSION.SDK_INT >= Build.VERSION_CODES.GINGERBREAD) {
			StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder().detectAll().penaltyDialog().build());
			StrictMode.setVmPolicy(new StrictMode.VmPolicy.Builder().detectAll().penaltyDeath().build());
		}

		super.onCreate();

		initImageLoader(getApplicationContext());
	}

	public static void initImageLoader(Context context) {
		// This configuration tuning is custom. You can tune every option, you may tune some of them,
		// or you can create default configuration by
		//  ImageLoaderConfiguration.createDefault(this);
		// method.
		ImageLoaderConfiguration.Builder config = new ImageLoaderConfiguration.Builder(context);
		//config.threadPoolSize(5)  //設置線程池的最高線程數量（1-5）（減少線程個數，有利於減少發生OOM）
		// 設置線程優先級（沒什麼用）
		config.threadPriority(Thread.NORM_PRIORITY - 2);
		// 設定內存緩存為弱緩存（該框架默認的緩存類是強引用緩存LruMemoryCache）
		config.memoryCache(new WeakMemoryCache());
		// 自動縮放
		config.denyCacheImageMultipleSizesInMemory();
		// 設定緩存到sd卡的文件的命名
		config.diskCacheFileNameGenerator(new Md5FileNameGenerator());
		// 設定緩存到sd卡的最大文件大小
		config.diskCacheSize(50 * 1024 * 1024); // 50 MiB
		config.tasksProcessingOrder(QueueProcessingType.LIFO);
		config.writeDebugLogs(); // Remove for release app

		// Initialize ImageLoader with configuration.
		ImageLoader.getInstance().init(config.build());
	}
}

關於強弱引用備注下

 

 

強引用是指創建一個對象並把這個對象賦給一個引用變量， 強引用有引用變量指向時永遠不會被垃圾回收。即使內存不足的時候寧願報OOM也不被垃圾回收器回收，我們new的對象都是強引用

弱引用通過weakReference類來實現，它具有很強的不確定性，如果垃圾回收器掃描到有著WeakReference的對象，就會將其回收釋放內存

 

本例的情況是

對於默認使用的強引用緩存（LruMemoryCache），采取的策略是，先進先出原則，設置一個固定緩存大小，當超出這個最大值時，刪除LinkedHashMap中的第一個元素

對於弱引用緩存（WeakMemoryCache），這個類緩存bitmap的總大小沒有限制，唯一不足的地方就是不穩定，緩存的圖片容易被回收掉

具體參考這篇分析詳細 http://blog.csdn.net/xiaanming/article/details/27525741

 

3，各個fragment

BaseFragment（用以給AbsListViewBaseFragment，ImageGalleryFragment，ImagePagerFragment繼承）（有兩個菜單項）

 

/*******************************************************************************
 * Copyright 2011-2014 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.fragment;

import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.sample.R;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
//基礎Fragment，創建菜單兩項，清除內存緩存和清除硬盤緩存
public abstract class BaseFragment extends Fragment {
	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		setHasOptionsMenu(true);
	}

	public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
		inflater.inflate(R.menu.main_menu, menu);
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
			case R.id.item_clear_memory_cache:
				ImageLoader.getInstance().clearMemoryCache();
				return true;
			case R.id.item_clear_disc_cache:
				ImageLoader.getInstance().clearDiskCache();
				return true;
			default:
				return false;
		}
	}
}

AbsListViewBaseFragment（用以給listview和gridview的fragment繼承的fragment）

 

主要有兩個關鍵的參數

//列表滾動是否暫停加載圖片
protected boolean pauseOnScroll = true;
//列表猛的滾動是否暫停加載圖片
protected boolean pauseOnFling = true;

 

/*******************************************************************************
 * Copyright 2011-2014 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.fragment;

import android.content.Intent;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.AbsListView;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.listener.PauseOnScrollListener;
import com.nostra13.universalimageloader.sample.Constants;
import com.nostra13.universalimageloader.sample.R;
import com.nostra13.universalimageloader.sample.activity.SimpleImageActivity;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
//要用於GridFragment和ListFragment，所以主要包括了通用的設置菜單方法，設置列表滑動是否暫停加載圖片的方法，以及傳遞item位置信息的方法
//因為gridview和listview都繼承自AbsListView，所以此類的listView也可以在GridFragment和ListFragment復用
public abstract class AbsListViewBaseFragment extends BaseFragment {

	protected static final String STATE_PAUSE_ON_SCROLL = STATE_PAUSE_ON_SCROLL;
	protected static final String STATE_PAUSE_ON_FLING = STATE_PAUSE_ON_FLING;

	protected AbsListView listView;
    //列表滾動是否暫停加載圖片
	protected boolean pauseOnScroll = true;
	//列表猛的滾動是否暫停加載圖片
	protected boolean pauseOnFling = true;

	@Override
	public void onResume() {
		super.onResume();
		applyScrollListener();
	}

	
	@Override
	public void onPrepareOptionsMenu(Menu menu) {
		MenuItem pauseOnScrollItem = menu.findItem(R.id.item_pause_on_scroll);
		pauseOnScrollItem.setVisible(true);
		pauseOnScrollItem.setChecked(pauseOnScroll);

		MenuItem pauseOnFlingItem = menu.findItem(R.id.item_pause_on_fling);
		pauseOnFlingItem.setVisible(true);
		pauseOnFlingItem.setChecked(pauseOnFling);
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		switch (item.getItemId()) {
			case R.id.item_pause_on_scroll:
				pauseOnScroll = !pauseOnScroll;
				item.setChecked(pauseOnScroll);
				applyScrollListener();
				return true;
			case R.id.item_pause_on_fling:
				pauseOnFling = !pauseOnFling;
				item.setChecked(pauseOnFling);
				applyScrollListener();
				return true;
			default:
				return super.onOptionsItemSelected(item);
		}
	}

	protected void startImagePagerActivity(int position) {
		Intent intent = new Intent(getActivity(), SimpleImageActivity.class);
		intent.putExtra(Constants.Extra.FRAGMENT_INDEX, ImagePagerFragment.INDEX);
		intent.putExtra(Constants.Extra.IMAGE_POSITION, position);
		startActivity(intent);
	}
    //滾動列表時，是否暫停加載圖片的監聽
    //第一個參數就是我們的圖片加載對象ImageLoader, 第二個是控制是否在滑動過程中暫停加載圖片，如果需要暫停傳true就行了，第三個參數控制猛的滑動界面的時候圖片是否加載
	private void applyScrollListener() {
		listView.setOnScrollListener(new PauseOnScrollListener(ImageLoader.getInstance(), pauseOnScroll, pauseOnFling));
	}
}
ImageListFragment

 

1，有關於DisplayImageOptions的設置，各情況加載的圖片以及緩存等的設置

在DisplayImageOptions選項中配置bitmapConfig為Bitmap.Config.RGB_565，因為默認是ARGB_8888， 使用RGB_565會比使用ARGB_8888少消耗2倍的內存

2，還有關於漸進動畫的設置AnimateFirstDisplayListener

 

/*******************************************************************************
 * Copyright 2011-2014 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.fragment;

import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
import com.nostra13.universalimageloader.core.display.RoundedBitmapDisplayer;
import com.nostra13.universalimageloader.core.listener.ImageLoadingListener;
import com.nostra13.universalimageloader.core.listener.SimpleImageLoadingListener;
import com.nostra13.universalimageloader.sample.Constants;
import com.nostra13.universalimageloader.sample.R;

import java.util.Collections;
import java.util.LinkedList;
import java.util.List;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
public class ImageListFragment extends AbsListViewBaseFragment {

	public static final int INDEX = 0;

	String[] imageUrls = Constants.IMAGES;

	DisplayImageOptions options;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		options = new DisplayImageOptions.Builder()
				.showImageOnLoading(R.drawable.ic_stub)
				.showImageForEmptyUri(R.drawable.ic_empty)
				.showImageOnFail(R.drawable.ic_error)
				.cacheInMemory(true)
				.cacheOnDisk(true)
				.considerExifParams(true)
				.displayer(new RoundedBitmapDisplayer(20))//設置圓角
				.build();
	}

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
		View rootView = inflater.inflate(R.layout.fr_image_list, container, false);
		//listView都是繼承自AbsListViewBaseFragment的listView
		listView = (ListView) rootView.findViewById(android.R.id.list);
		((ListView) listView).setAdapter(new ImageAdapter());
		listView.setOnItemClickListener(new OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView parent, View view, int position, long id) {
				startImagePagerActivity(position);
			}
		});
		return rootView;
	}

	@Override
	public void onDestroy() {
		super.onDestroy();
		AnimateFirstDisplayListener.displayedImages.clear();
	}

	private static class ViewHolder {
		TextView text;
		ImageView image;
	}

	class ImageAdapter extends BaseAdapter {

		private LayoutInflater inflater;
		private ImageLoadingListener animateFirstListener = new AnimateFirstDisplayListener();

		ImageAdapter() {
			inflater = LayoutInflater.from(getActivity());
		}

		@Override
		public int getCount() {
			return imageUrls.length;
		}

		@Override
		public Object getItem(int position) {
			return position;
		}

		@Override
		public long getItemId(int position) {
			return position;
		}

		@Override
		public View getView(final int position, View convertView, ViewGroup parent) {
			View view = convertView;
			final ViewHolder holder;
			if (convertView == null) {
				view = inflater.inflate(R.layout.item_list_image, parent, false);
				holder = new ViewHolder();
				holder.text = (TextView) view.findViewById(R.id.text);
				holder.image = (ImageView) view.findViewById(R.id.image);
				view.setTag(holder);
			} else {
				holder = (ViewHolder) view.getTag();
			}

			holder.text.setText(Item  + (position + 1));

			ImageLoader.getInstance().displayImage(imageUrls[position], holder.image, options, animateFirstListener);

			return view;
		}
	}
    //設圖片第一次加載完成的漸入動畫
	//取得加載完成圖片的uri，看是否在已經顯示的圖片列表中，沒有即第一次則顯示加載動畫並加入到顯示列表
	private static class AnimateFirstDisplayListener extends SimpleImageLoadingListener {

		static final List displayedImages = Collections.synchronizedList(new LinkedList());

		@Override
		public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
			if (loadedImage != null) {
				ImageView imageView = (ImageView) view;
				boolean firstDisplay = !displayedImages.contains(imageUri);
				if (firstDisplay) {
					FadeInBitmapDisplayer.animate(imageView, 500);
					displayedImages.add(imageUri);
				}
			}
		}
	}
}

ImageGridFragment

 

顯示加載進度的監聽SimpleImageLoadingListener

 

/*******************************************************************************
 * Copyright 2011-2014 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.fragment;

import android.graphics.Bitmap;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ProgressBar;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.assist.FailReason;
import com.nostra13.universalimageloader.core.listener.ImageLoadingProgressListener;
import com.nostra13.universalimageloader.core.listener.SimpleImageLoadingListener;
import com.nostra13.universalimageloader.sample.Constants;
import com.nostra13.universalimageloader.sample.R;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
public class ImageGridFragment extends AbsListViewBaseFragment {

	public static final int INDEX = 1;

	String[] imageUrls = Constants.IMAGES;

	DisplayImageOptions options;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		options = new DisplayImageOptions.Builder()
				.showImageOnLoading(R.drawable.ic_stub)
				.showImageForEmptyUri(R.drawable.ic_empty)
				.showImageOnFail(R.drawable.ic_error)
				.cacheInMemory(true)
				.cacheOnDisk(true)
				.considerExifParams(true)
				.bitmapConfig(Bitmap.Config.RGB_565)
				.build();
	}

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
		View rootView = inflater.inflate(R.layout.fr_image_grid, container, false);
		listView = (GridView) rootView.findViewById(R.id.grid);
		((GridView) listView).setAdapter(new ImageAdapter());
		listView.setOnItemClickListener(new OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView parent, View view, int position, long id) {
				startImagePagerActivity(position);
			}
		});
		return rootView;
	}

	public class ImageAdapter extends BaseAdapter {

		private LayoutInflater inflater;

		ImageAdapter() {
			inflater = LayoutInflater.from(getActivity());
		}

		@Override
		public int getCount() {
			return imageUrls.length;
		}

		@Override
		public Object getItem(int position) {
			return null;
		}

		@Override
		public long getItemId(int position) {
			return position;
		}

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			final ViewHolder holder;
			View view = convertView;
			if (view == null) {
				view = inflater.inflate(R.layout.item_grid_image, parent, false);
				holder = new ViewHolder();
				assert view != null;
				holder.imageView = (ImageView) view.findViewById(R.id.image);
				holder.progressBar = (ProgressBar) view.findViewById(R.id.progress);
				view.setTag(holder);
			} else {
				holder = (ViewHolder) view.getTag();
			}
            //這裡有顯示圖片加載進度的方法
			ImageLoader.getInstance()
					.displayImage(imageUrls[position], holder.imageView, options, new SimpleImageLoadingListener() {
						@Override
						public void onLoadingStarted(String imageUri, View view) {
							holder.progressBar.setProgress(0);
							holder.progressBar.setVisibility(View.VISIBLE);
						}

						@Override
						public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
							holder.progressBar.setVisibility(View.GONE);
						}

						@Override
						public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
							holder.progressBar.setVisibility(View.GONE);
						}
					}, new ImageLoadingProgressListener() {
						@Override
						public void onProgressUpdate(String imageUri, View view, int current, int total) {
							holder.progressBar.setProgress(Math.round(100.0f * current / total));
						}
					});

			return view;
		}
	}

	static class ViewHolder {
		ImageView imageView;
		ProgressBar progressBar;
	}
}

ImagePagerFragment

 

注意在此Fragment中通過getArguments方法取得在SimpleImageActivity中setArguments的position的值，對應正確的條目

 

/*******************************************************************************
 * Copyright 2011-2014 Sergey Tarasevich
 *
 * Licensed under the Apache License, Version 2.0 (the License);
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an AS IS BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *******************************************************************************/
package com.nostra13.universalimageloader.sample.fragment;

import android.graphics.Bitmap;
import android.os.Bundle;
import android.os.Parcelable;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.Toast;
import com.nostra13.universalimageloader.core.DisplayImageOptions;
import com.nostra13.universalimageloader.core.ImageLoader;
import com.nostra13.universalimageloader.core.assist.FailReason;
import com.nostra13.universalimageloader.core.assist.ImageScaleType;
import com.nostra13.universalimageloader.core.display.FadeInBitmapDisplayer;
import com.nostra13.universalimageloader.core.listener.SimpleImageLoadingListener;
import com.nostra13.universalimageloader.sample.Constants;
import com.nostra13.universalimageloader.sample.R;

/**
 * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
 */
public class ImagePagerFragment extends BaseFragment {

	public static final int INDEX = 2;

	String[] imageUrls = Constants.IMAGES;

	DisplayImageOptions options;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);

		options = new DisplayImageOptions.Builder()
				.showImageForEmptyUri(R.drawable.ic_empty)
				.showImageOnFail(R.drawable.ic_error)
				.resetViewBeforeLoading(true)
				.cacheOnDisk(true)
				.imageScaleType(ImageScaleType.EXACTLY)
				.bitmapConfig(Bitmap.Config.RGB_565)
				.considerExifParams(true)
				.displayer(new FadeInBitmapDisplayer(300))
				.build();
	}

	@Override
	public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
		View rootView = inflater.inflate(R.layout.fr_image_pager, container, false);
		ViewPager pager = (ViewPager) rootView.findViewById(R.id.pager);
		pager.setAdapter(new ImageAdapter());
		//在Fragment中取出傳過來的值getArguments()返回bundle
		pager.setCurrentItem(getArguments().getInt(Constants.Extra.IMAGE_POSITION, 0));
		return rootView;
	}

	private class ImageAdapter extends PagerAdapter {

		private LayoutInflater inflater;

		ImageAdapter() {
			inflater = LayoutInflater.from(getActivity());
		}

		@Override
		public void destroyItem(ViewGroup container, int position, Object object) {
			container.removeView((View) object);
		}

		@Override
		public int getCount() {
			return imageUrls.length;
		}

		@Override
		public Object instantiateItem(ViewGroup view, int position) {
			View imageLayout = inflater.inflate(R.layout.item_pager_image, view, false);
			assert imageLayout != null;
			ImageView imageView = (ImageView) imageLayout.findViewById(R.id.image);
			final ProgressBar spinner = (ProgressBar) imageLayout.findViewById(R.id.loading);

			ImageLoader.getInstance().displayImage(imageUrls[position], imageView, options, new SimpleImageLoadingListener() {
				@Override
				public void onLoadingStarted(String imageUri, View view) {
					spinner.setVisibility(View.VISIBLE);
				}

				@Override
				public void onLoadingFailed(String imageUri, View view, FailReason failReason) {
					String message = null;
					switch (failReason.getType()) {
						case IO_ERROR:
							message = Input/Output error;
							break;
						case DECODING_ERROR:
							message = Image can't be decoded;
							break;
						case NETWORK_DENIED:
							message = Downloads are denied;
							break;
						case OUT_OF_MEMORY:
							message = Out Of Memory error;
							break;
						case UNKNOWN:
							message = Unknown error;
							break;
					}
					Toast.makeText(getActivity(), message, Toast.LENGTH_SHORT).show();

					spinner.setVisibility(View.GONE);
				}

				@Override
				public void onLoadingComplete(String imageUri, View view, Bitmap loadedImage) {
					spinner.setVisibility(View.GONE);
				}
			});

			view.addView(imageLayout, 0);
			return imageLayout;
		}

		@Override
		public boolean isViewFromObject(View view, Object object) {
			return view.equals(object);
		}

		@Override
		public void restoreState(Parcelable state, ClassLoader loader) {
		}

		@Override
		public Parcelable saveState() {
			return null;
		}
	}
}

 

 



 


 

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